1. Field of the Invention
The present invention pertains to containers of the type which are constructed without adhesive by folding a one-piece blank of corrugated cardboard or other suitable material.
2. Description of the Related Art
Many users of cartons made from corrugated cardboard and the like material who operate mass production facilities prefer to receive shipping cartons in an unassembled or "knocked-down" condition. Further, certain economies of carton manufacture can be obtained if the carton is constructed from a unitary blank. Accordingly, such cartons may be supplied to customers in the form of a stack of sheet-like carton blanks which are stacked on a pallet. Palletized carton blanks are attractive to a carton user since a large number of cartons can be erected from a palletized load and the pallets can be located close to a production line since they require a minimum of space. It is important however, that such cartons be quickly and easily erected so as to coordinate with the rate of production of the products to be stored in the cartons.
One example of a mass production application for palletized cartons is found in the meat packing industry. Such cartons are used to transport cuts of meat to a nearby freezing area, or frozen meat cuts can be placed directly into the cartons. As mentioned, the cartons, if they are to be useful in a mass production, high production rate environment must be quickly and easily erected from the flat blank.
It is generally preferred that adhesive be avoided in the erection of the carton blanks, since the use of adhesive slows the erection process, both in application of the adhesive and in the time required for the adhesive to cure or set. Further, carton users prefer cartons which are erected without adhesive since adhesive requires additional machinery located proximate to the assembly line, where space is at a premium. Further, if adhesive can be avoided in the carton erection, additional control practices required in the food processing industries can be avoided.
Cartons used for packaging meat cuts and other high density (and therefore heavy) products must, even though erected without adhesive, be strong enough to withstand relatively high loadings. Further, cartons used in the meat packing industry and in many other industries are loaded in bulk onto box cars and trucks, by being stacked one on top of another. The loading on the lower level of cartons can at times be quite high. It is important that cartons successfully withstand the rigors of conventional shipping practices if losses to the carton users are to be avoided.